diff --git a/contrib/jj-am.sh b/contrib/jj-am.sh
new file mode 100755
index 0000000..8fb73dd
--- /dev/null
+++ b/contrib/jj-am.sh
@@ -0,0 +1,58 @@
+#!/usr/bin/env bash
+# This Source Code Form is licensed MPL-2.0: http://mozilla.org/MPL/2.0
+set -Eeuo pipefail #-x
+SCRIPTNAME=`basename $0` && function die  { [ -n "$*" ] && echo "$SCRIPTNAME: **ERROR**: ${*:-aborting}" >&2; exit 127 ; }
+VERSION=0.0.1-alpha
+
+# == Parse Options ==
+MBOXES=()
+while test $# -ne 0 ; do
+  case "$1" in \
+    --version)  echo "$SCRIPTNAME $VERSION"; exit ;;
+    -*)		die "unknown option: $1" ;;
+    *)		MBOXES+=("$1") ;;
+  esac
+  shift
+done
+
+# == Functions ==
+# Create temporary dir, assigns $TEMPD
+temp_dir()
+{
+  test -n "${TEMPD:-}" || {
+    TEMPD="`mktemp --tmpdir -d $SCRIPTNAME-XXXXXX`" || die "mktemp failed"
+    trap "rm -rf '$TEMPD'" 0 HUP INT QUIT TRAP USR1 PIPE TERM
+    echo "$$" > $TEMPD/$SCRIPTNAME.pid
+  }
+}
+# Create new commit
+jj_commit()
+(
+  # collect commit infor from header
+  HEADER="$1" BODY="$(<"$2")" PATCH="$3"
+  AUTHOR="$(sed -nr '/^Author: /{ s/^[^:]*: //; p; q; }' < $HEADER)"
+  EMAIL="$(sed -nr '/^Email: /{ s/^[^:]*: //; p; q; }' < $HEADER)"
+  DATE="$(sed -nr '/^Date: /{ s/^[^:]*: //; p; q; }' < $HEADER)"
+  DATE="$(date --rfc-3339=ns -d "$DATE")"
+  SUBJECT="$(sed -nr '/^Subject: /{ s/^[^:]*: //; p; q; }' < $HEADER)"
+  export JJ_TIMESTAMP="$DATE"
+  test -z "$BODY" && NL='' || NL=$'\n\n'
+  ARGS=(
+    --config-toml "user.name=\"$AUTHOR\""
+    --config-toml "user.email=\"$EMAIL\""
+    --message="$SUBJECT$NL$BODY"
+  )
+  # try patch
+  patch -p1 < "$PATCH"
+  # apply
+  jj new "${ARGS[@]}"
+)
+
+# == Process ==
+temp_dir	# for $TEMPD
+for mbox in "${MBOXES[@]}" ; do
+  echo "Apply: ${mbox##*/}"
+  rm -f "$TEMPD/header" "$TEMPD/body" "$TEMPD/patch"
+  git mailinfo -b -u --encoding=POSIX.UTF-8 "$TEMPD/body" "$TEMPD/patch" > "$TEMPD/header" < "$mbox"
+  jj_commit "$TEMPD/header" "$TEMPD/body" "$TEMPD/patch"
+done